GitHub is pretty easily the most unreliable service I've used in the past five years. Is GitLab better in this regard? At this point my trust in GitHub is essentially zero - they don't deserve my money any longer.
My company self-hosts GitLab. Gitaly (the git server) is a weekly source of incidents, it doesn't scale well (CPU/memory spikes which end up taking down the web interface and API). However we have pretty big monorepos with hundreds of daily committers, probably not very representative.
We self host gitlab, so its very stable. But Gitlab also kind of is enterprise software. It hits every feature checkbox, but they aren't well integrated, and they are kind of half way done. I don't think its as smooth of an experience as Github personally, or as feature rich. But Gitlab can self host your project repos, cicd, issues, wikis, etc. and it does it at least okay.
Frequently use both `github.com` and self-hosted Gitlab. IMHO, it's just... different.
Self-hosted Gitlab periodically blocks access for auto-upgrades.
Github.com upgrades are usually invisible.
Github.com is periodically hit with the broad/systemic cloud-outage.
Self-hosted Gitlab is more decentralized infra, so you don't have the systemic outages.
With self-hosted Gitlab, you likely to have to deal with rude bots on your own.
Github.com has an ops team that deals with the rude bots.
We self-host GitLab but the team owning it is having hard time scaling it. From my understanding talking to them, the design of gitaly makes it very hard to scale it beyond certain repo size and # of pushes per day (for reference: our repos are GBs in size, ~1M commits, hundreds of merges per day)
We've been self hosting GitLab for 5 years and it's the most reliable service in our organization. We haven't had a single outage. We use Gitlab CI and security scanning extensively.
Ditto, self-hosted for over eight years at my last job. SCM server and 2-4 runners depending on what we needed. Very impressive stability and when we had to upgrade their "upgrade path" tooling was a huge help.
Another GitLab self-hosting user here, we've run it on Kubernetes for 6 years. It's never gone down for us, maybe an hour of downtime yearly as we upgrade Postgres to a new version.
GitLab is slow and its pages are heavy. I often have to work on slow/unreliable internet and GitLab pages simply can’t finish loading. Most of them need to load megabytes of JavaScript before they even fetch the data to be shown. The data being usually under 1kB of text.
Gitlab has regular issues (we use Saas) and the support isn’t great. They acknowledge problems, but the same ones happen again and again. It’s very hard to get anything on their roadmap etc.